Infinitely variable electronic device

ABSTRACT

TWO ELECTRICAL ELEMENTS ARE MOUNTED FOR INDEPENDENT ROTATION IN THE SAME DIRECTION ABOUT A COMMON AXIS AND, AS A RESULT OF THE ROTATION, A LONGITUDINAL DISPLACEMENT WITH RESPECT TO EACH OTHER, SAID ELEMENTS BEING IN ELECTRICALLY COACTIVE RELATIONSHIP WHEREBY ELECTRICAL VALUES DEPEND UPON THE LONGITUDINAL DISPLACEMENT CAUSED BY THE ROTATION OF THE TWO ELEMENTS.

Feb. 2, 1971 E. c. WAHLBERG 3,560,906

- INFINITELY VARIABLE ELECTRONIC DEVICE Filed 001;. 28, 1968 IlllPatented Feb. 2, 1971 3,560,906 INFINITELY VARIABLE ELECTRONIC DEVICEEric C. Wahlberg, 32 8th St., Stamford, Conn. 06905 Filed Oct. 28, 1968,Ser. No. 771,126 Int. Cl. H01c /02, I/02 U.S. Cl. 338-145 6 ClaimsABSTRACT OF THE DISCLOSURE This invention relates to electronic devicesnormally known as potentiometers, variable resistors, variablecondensors, trimmers, variable impedances and the like. In particular,as described herein but not limited thereto, the invention relates toproviding a simple, economical, miniature assembly which will result inproviding extremely accurate electrical values for electronic and otherdevices.

An object of the invention is to provide a means whereby the pickoffcontact follows each minute increment of the length of the resistivelayer thus providing extreme accuracy.

Another object is to provide a product which is vibration and shockproof and will not lose its accurate setting under such conditions.

Another object of the invention is to provide a product with a minimumof parts designed for simple and quick assembly. Another object of thisinvention is to provide a product which is adaptable to incorporating asingle electrical characteristic or a multiple of the same or difierentcharacteristics into one unit.

Further objects of the invention will become apparent from the broadinterpretation of the specification and the drawings.

These and other objects of the invention are achieved in an arrangementwherein two cylinders, each having a body and a flange at one end of thebody, the flanges being of different diameters but larger than therespective body diameters, are free to rotate about a common shaftcenter. The circumference of the body of one cyclinder has a threadwhich mates with an internal thread of the body of the second cylinder.When the flanges of the two cylinders are mated with a third memberhaving correspondingly different diameters, a rotation of the twocylinders with respect to each other may be caused by the turning of thethird member. The radius of one flange added to the radius of thatportion of the third member which cooperates with that flange must equalthe radius of the other flange added to the radius of that portion ofthe third member which cooperates with that flange, and, as a result,the relative speed of rotation of one cylinder with respect to the othercylinder will be determined by the ratio between their respective radii.The net effective result of the difference in speed will be translatedinto a longitudinal displacement of the two cylinders relative to eachother. Proper mounting of the conducting components and the one cylinderand sliding pick-off on the mating cylinder coact together withterminals, cylinder shafts and pinion shaft to provide an assembly whichmay be compactly contained in a housing to form a completed productaccording to this invention.

One embodiment of this invention is illustrated in FIGS. 1-5 in which:

FIG. 1 illustrates a front view of the complete unit;

FIG. 2 is a view showing the assembly in a cutaway of the housing;

FIG. 3 is a top view with the cover removed;

FIG. 4 is a cross section of the two cylinders and their components asthey relate to the assembly in a cross section of the housing along line4-4 of FIG. 3;

FIG. 5 is a cross section taken along line '55 of FIG. 4; and

FIG. 6 is a cross section view of segment of the cylinder and driveassembly illustrating a second embodiment.

Other embodiments of this invention are afforded with variablecondensers, impedances, etc., as well as multiple electrical componentsoperated by one drive member in which mounting of the rotary andstationary parts on the respective cylinders is accomplished so thatwhen they are rotated they are properly identified with each other as toelectrical properties and mechanically. It is important therefore not tolimit the scope of the invention to those embodiments illustrated but toconsider it in the broad aspect.

Reference is now made to FIG. 4 which illustrates the parts involved inthe assembly of the embodiment. Included in the embodiment is case 50with cover 6, shaft 24, lower cylinder 14, upper cylinder 33, pinionshaft 16, terminals 7, 21, 20, sliding contacts 15, 28, 27, conductivelayers 23 and 25, and resistive layer 10 in the root of the worm teeth9. Cylinders 14, 33, pinion 16, shaft 24, housing 50 and cover 6 aremade of insulating material.

Sliding contact 15 is mounted in longitudinal groove 34 on thecircumference of cylinder 14. One end contacts conductive layer 10 inthe threaded circumference of cylinder 33. The threads are deep enoughso that when the resistance is in place at the root of the thread themating thread of cylinder 14 does not extend against the resistance pathor layer. The other end of slide contact 15 extends under the cylinder14 and around the insulator 19. An extruded washer 18, FIG. 5 havingfour equally spaced fingers 30 biased upwardly so that when the partsare in place there will be a spring action against the bottom of thecase to force the cylinder assembly together against the cover and toassure good contact between the washer and the sliding contact extension31. The washer has a tubular extension projecting downwardly to form acontact 20 which extends out of the case 50. The resistive layer 9 isdeposited in the root of the thread on the circumference of cylinder 33.A sliding contact 28 is snapped around the lower end of cylinder 33holding the lower end of the resistive layer. The other end is inslidable contact with conductive layer 23 surrounding the lower end ofinsulating shaft 24. The conductive layer 23 has an extension whichforms a terminal 21 and extends through the bottom of cylinder 14 andcontact 20 which is insulated from terminal 21 by tube 19. Anothersliding contact 27 is snapped around the upper end of cylinder 33. Oneend is attached to the upper end of the resistive layer and the otherend is in slidable contact with conductive layer 25 surrounding theupper end of the insulated shaft 24. An enlargement 29 of the diameterof insulating shaft 24 separates the conducting layers 23 from 25. Thecon ductive layer 25 has an extension which forms a terminal 7 extendingout of the cover 6. Thus, two terminals extend out of the bottom of thecase and the third terminal extends out of the cover of the case and arestationary.

A circuit is made from terminal 7 through conductive layer 25, contact27, resistive layer 10, slidable contact 15, washer 18 to contact 20.Also a circuit is made from terminal 7, conductive layer 25, contact 27,resistive layer 10, contact 28, conductive layer 23 and terminal 21. Theamount of resistance included in the first path is determined by theposition of contact 15 on the resistive layer 10. This in turn isdependent on the relative longitudinal positions of the cylinders 14 and33. Their positions are determined by the turning of the pinion shaft16.

Cylinder 33 has a thread on its circumference whose teeth 9 mate andcoact with thread teeth 26 on the inner wall of the lower cylinder 14.The upper cylinder also has a flange extending outwardly from the upperend of the cylinder. This flange has spur teeth 8 which rotatably andslidably mate with teeth 11 on pinion shaft 16. The lower cylinder 14also has a set of spur teeth located tround the circumference of theupper end of the cylinder. These teeth mate with a second set of teeth12 on the pinion 16. The teeth 11 are located on a diameter which islarger than the diameter on which gear teeth 12 are located. The gearteeth on the larger diameter of the pinion are mated with the gear teethon the smaller cylinder, in the upper cylinder 33. The gear teeth on thesmaller diameter of the pinion shaft 16 are mated to the teeth on thelarge diameter cylinder 14. In each case the sum of the pitch radii ofthe pinion and the cylinder gear teeth must equal the center distancebetween the pinion shaft 16 center and insulated shaft 24 center. Thus,when the pinion shaft is turned by means of extension 17, both cylinderswill rotate and in proportion to the circumferences of the mating gears.The larger cylinder 14 will turn slower than the smaller cylinder 33.Thus, though both cylinders are rotating, the smaller cylinder 33 willbe going faster and, after a predetermined number of turns of the pinionshaft 16, will lap cylinder 14.

Since cylinder 33 Will be turning faster than cylinder 14, cylinder 33will screw itself down into cylinder 14 by means of the coaction ofteeth 9 On cylinder 33 and teeth 26 on cylinder 14 as they are mated.Thus, with proper design, very high accuracy may be obtained from smallincrements of rotation of the pinion shaft applied to displace thecylinders 14 and 33 angularly and consequentially, longitudinally.

An extension 22 on one end of the pinion shaft 16 is provided as abearing surface in the bottom of the case 5. At the other end of thepinion an extension 17 is provided as a second bearing to fit intoopening in cover 6. This extension is a means for applying motion to thepinion either manually or by motor drives etc. for remote control.

The above parts are assembled into case equipped with cover 6.

By providing threads the entire length of the inside of the lowercylinder and by placing a conductive path in the root of the thread ofthe upper cylinder and by connecting contact directly to theaforementioned conductive path in the lower cylinder 14, a condenser iseffected.

Another means of obtaining condenser action is to provide a conductivepath inside of the upper cylinder 33 and removing contact 28. In thisway an electrical coaction obtained between the conductive path on theinside of the upper cylinder and the conductive path 23 of the shaft 24.

Several combinations may be obtained by the use of both conductive,inductive and noninductive electrical material mounted on the cylindersto coact to give the desired electrical characteristics.

To those skilled in the art, it will be readily understood that aplurality of sets of mating cylinders, such as 14 and 33, with theircomponents may be rotated simultaneously by mating with the respectivegear teeth of the pinion shaft 16 and by rotating the pinion shaft 16;that a number of combinations of speeds may be developed with properdesign of coacting components; that a number of electricalcharacteristics capable of being varied by the application of thisconcept may be obtained all as required to fulfill the specific designcriteria.

The operation of the described embodiment is simple. An electrical powersource is connected across terminals 7 and 21. As shaft extension 17 isturned in one direction, the cylinder 33 will be caused to rotate bygear 11 and 8 around shaft 24. Cylinder 14 will also be caused to rotateby gears 12 and 13 about shaft 24. Cylinder 14 will rotate at a lesserspeed rate than cylinder 33. The difference of rates of speed istranslated into a longitudinal motion of cylinder 33 into cylinder 14through the action of thread 9 of cylinder 33 against thread 26 ofcylinder 14. Since cylinder 14 is restricted in its longitudinal motionby its position between the bottom of the case and the shoulder of theend of the shaft 24, all the longitudinal motion is accomplished bycylinder 33. Therefore, gear 8 will move longitudinally along piniongear 11 a proportionate amount as it rotates with gear 11. Further,contacts 27 and 28 move around angularly and longitudinally along theconductive coatings 25 and 23 respectively on shaft 24 so thatcontinuity of power is preserved to resistive layer 10. As cylinders 14and 33 rotate and move longitudinally, sliding contact 15 in cylinder 14follows the resistive layer and monitors the electrical change thattakes place. This change is transmitted to terminal 20 so that anelectrical value may be continually obtained across terminals 7 and 20or 20 and 21.

When the extension 17 of pinion shaft 16 is in the opposite direction,cylinders 33 and 14 will reverse their operation and the same terminalswill indicate the change in the direction by an appropriate change inelectrical output.

Referring to FIG. 6, which illustrates, when taken in combination withFIG. 4, another embodiment of the invention. Included in the embodimentis a case 50, cover 6, shaft 240, lower cylinder 14, upper cylinder 330,pinions 11 and 12, and lock ring 51. Like numerals designate like partsin both embodiments illustrated.

Cylinder 330 has a thread on the circumference of its lower portionwhose teeth 9 mate and coact with thread teeth 26 on the inner wall ofthe lower cylinder 14. The upper cylinder also has a flange extendingoutwardly from the central portion of the cylinder. This flange has spurgear teeth 8 rotatably and slidably mating with teeth 11 on pinion shaft16 of FIG. 4. The upper cylinder extends out of the cover 6 and isfitted on its outer end with a connecting tongue 55 having a pin 53 as ameans for connectrng to some such mechanism 54. Upper cylinder 330 1sprovided with an internal bore which provides means for mountingallowing angular and longitudinal motion on shaft 240.

The lower cylinder 14 also has a set of teeth 13 located around thecircumference of the upper end of the cylinder. These teeth mate with asecond set of teeth 12 on the pinion 16. The lower cylinder is mountedon a smaller diameter at the end of shaft 240.

The entire assembly of the upper and lower cylinders and the pinion ismounted in the case 50 by means of the shaft 240 extending through thebottom of case 50. A snap ring 51 is placed in groove 52 of shaft 240 toanchor the assembly in the case 50. A cover 6 is provided to encloseassembly allowing only the extension of the pinion shaft and theextension of the upper cylinder 330 to protrude.

The interaction and resultant displacement of the two cylinders by themotion of the pinion is the same as for the embodiment previouslydescribed and is therefore not repeated.

However, the resultant longitudinal and angular displacement of theupper cylinder 330 provides a means for operating various devices whichrequire accurate straight line or a combination of straight line androtary motion.

There accordingly have been shown and described herein novel means forobtaining highly accurate positioning means for obtaining highlyaccurate positioning of various items particularly of mechanical,electronic or electrical nature but not limited thereto. There has beendescribed and shown a novel means of accurately rotating two or moreitems at relative speeds to each other and to accurately displace eachother longitudinally with regard to each other. There has also beendescribed a means for obtaining accurate electrical values by accuratelyand infinitely varying the relative positions of coacting electricalelements. There has also been described a means of employing a pluralityof such devices operated from one input.

While I have described several embodiments of my invention in thisapplication, it is not the intent to limit the scope of the invention tothese embodiments as there are other embodiments that may be made bythose skilled in the art without departing from the concept of theinvention.

What I claim is:

1. A device for connection in an electrical circuit for adjusting to aselected electrical value from a multiplicity of electrical values insaid circuit, comprising a housing, a pair of elements mounted in saidhousing in electrical coactive relationship with each other andindependently rotating while in said coactive relationship about acommon axis and for motion longitudinally with respect to each other,each of said multiplicity of electrical values being a function of therelative angular and longitudinal displacement of said pair of elements,and driving means for simultaneously rotating both of said pair ofelements in the same direction, said driving means including a rotatabledrive member engageable with each of said pair of elements for angulardisplacement of, said elements in response to rotation of said drivemember, means for longitudinally displacing said pair of elements withrespect to each other in response to the rotation of each of saidelements by said drive member, the rate of longitudinal displacement ofsaid pair of elements with respect to each other being determined by thedifference of the angular rate of each of said pair of elements.

2. The device as defined in claim 1 wherein the first one of said pairof elements comprises a cylindrical shaped body mounted for rotationabout a central axis having a threaded peripheral surface, a resistivelayer disposed in said peripheral surface, and the second one of saidpair of elements comprising a cylindrical body having an internal threadcoacting with the threads of said first one of said pair of elements forlongitudinal movement relative to each other, said second pair ofelements includes contact means rotatable therewith and in electricaloperative engagement with said resistive layer.

3. The device as defined in claim 1 wherein said drive means includes apair of coaxial gear means mounted on an axis parallel with said commonaxis each having a different radius, and a pair of driven gear means ofunequal radii in driven engagement with the first pair of gear means,and means for operatively connecting each 6 of said driven gear meanswith a respective one of said first mentioned pair of elements.

4. The device as defined in claim 1 wherein each of said pair ofelements comprises a cylindrically shaped body rotating about itscentral axis, and said driving member is rotating about an axis parallelwith said common axis of rotation of the pair of elements, said drivingelement having two circumferential portions of unequal radii, and meansfor driving engagement between said driving portions and acircumferential portion of a respective cylindrical shaped element, thesum of the radius of one driving portion and the radius of a respectiveelement being equal to the sum of the radius of the other drivingportion and the radius of the other respective element.

5. The device as defined in claim 4 wherein said two drive portionscomprise spur gears, and the circumferential portions of the pair ofelements include teeth for meshing engagement with said spur gears.

6. A device for connection to a mechanism for adjusting to a selectedelectrical value from a multiplicity of electrical values in saidmechanism, comprising a housing, a pair of elements mounted in saidhousing in coactive relationship with each other and independentlyrotating while in said coactive relationship about a common axis and formotion longitudinally with respect to each other, each of saidmultiplicity of electrical values being a function of the relativeangular and longitudinal displacement of said pair of elements, anddriving means simultaneously rotating both of said pair of elements inthe same direction, said driving means including a rotatable drivemember engageable with each of said pair of elements for angulardisplacement of said elements in response to rotation of said drivemember, means for longitudinally displacing said pair of elements withrespect to each other in response to the rotation of each of saidelements by said drive member, the rate of longitudinal displacement ofsaid pair of elements with respect to each other being determined by thediflerence of the angular rate of rotation of each of said pair ofelements.

References Cited UNITED STATES PATENTS 2,785,261 3/1957 Roberts 338157X3,109,317 11/1963 Cousino 7441l 3,360,757 12/1967 Wahlberg 338-162 LEWISH. MYERS, Primary Examiner G. P. TOLIN, Assistant Examiner US. Cl. X.R.338-146, 162, 174

